Permutation pin tumbler lock



F. CHIN PERMUTATION PIN TUMBLER LOCK Filed Nov. 21, 1929 NVENTOR 6 Patented Dec. 16, 1941 UNITED STATES PATENT OFFICE 2,266,163 l PERMUTATION PIN TUMBLER LooK John Ching, Berkeley, Calif. Application November 21, 1939, Serial No. 305,489

(o1. iii- 382) 4 Claims.

This invention relates to key-operated locks and particularly to the species thereof commonly known as pin tumbler locks.

It is an object of the invention to provide a lock of the class described whose. combination may be readily changed without disassembling the lock. 1 I

Another object of the invention is to provide a lock of the pin tumbler variety in which at least one set of tumblers may be displaced relative to the positions of other sets of tumblers so as to change the combination of the lock.

A further object of the invention is to provide a lock of the class described whose combination may easily be changed by a person not possessing a great deal of mechanical skill.

The invention possesses other objects and features of advantage, some of which, together with the foregoing, will be specifically set forth in the detailed description of the invention hereunto annexed. It is to be understood that the invention is not to be limited to the specific form thereof herein shown and described as various other embodiments thereof may be employedwithin the scope of the appended claims.

Referring to the drawing:

Figure l is a vertical sectional view taken longitudinally through a lock, of the rotary-barrel pin-tumbler type, showing the improvements of my invention incorporated therein.

Figure 2 is a vertical sectional view of the lock. The plane in which the view is taken is indicated by the line 2-2 of Figure 1.

v Figure 3 is a vertical sectional view of the lock. The plane in which the View is taken is indicated by the line 3-3 of Figure l.

The common familiar pin-tumbler lock comprises a unitary barrel provided with a longitudinal bore in which the key-receiving lock rotor is rotatably journaled. The rotor is provided with a plurality, usually five, of longitudinally spaced radial bores in which ar slidably mounted short sections of round rods forming halves of the lock tumblers. Similar short rods are slidably mounted in bores in the barrel which are similarly spaced with, and adapted to be brought into axial registry with the bores of the rotor as the latter is rotated. Springs are usually provided in each bore so. as to maintain the two rod sections of each tumber in abutting relation. The key provided for operating such'a lock has usually five notches of various depths cut into one edge thereof so that upon insertion of the key in the keyway provided therefor in.

the lock rotor, each tumbler will be moved to assume a position in its bore whichis slightly different from that of its neighbor and the/depths of the key notches and lengths of the lower sections of the tumblers are made so that theplane of division of each tumbler will be brought to coincide with the periphery of the rotor. The rotor is thus free to bexrotated; carrying Wlt1fl it the lower section of each tumbler. Whenthe rotor is brought back to normal position, wherein the tumbler bores of the barrel androtor are in alinement, and the key is withdrawn from the rotor, the upper sections of the tumblers will fall or be spring pressed partly into the bores of the rotor thus pinning the rotor and the barrel together so that the rotor may not be there-- after rotated unless the proper key is used to unlock it. p

Frequently a key is lost and in order to preelude unauthorized opening of the lock by anyone who happens to find the key, it is necessary to change the combination thereof. This usu ally requires the services of -a skilled locksmith who dismantles the lock, makes a new key in which the depth of one or more of the tumbler notches is altered, places the new key'in' the rotor, fits th lower section of each tumbler so that it will terminate flush with the periphery of the rotor, and then reassembles the lock. It will be seen that work of this nature is beyond the skill of the ordinary person, consumes considerable time and is consequently quite costly. I have provided a lock structure which permits the lock combination to be repeatedly changed as desired Without the necessity of taking the lock apart or altering the tumblers and-which permits this adjustment to be done by a person possessing no great mechanical skill. 1

Describing my invention in detail, I provide a tubular sleeve 4 having adjacent an end thereof external screw threads 6, and being provided in the interior thereof with a bore 1, internal screw threads 8, and a counterbor 9. The end of the bore 1 is provided with'an inwardly directed flange ll. Journaled in'the counterbore 9, for rotation with respect to the sleeve-4, is

a cylindrical lock barrel I2 having an end flange I3 which abuts against the endof =the'sleeve 4 so as to prevent relative axial displacement between the barrel and the sleeve in onevdirection.

The lock barrel is provided with a peripheral groove 14, and setscrewslt tapped radially through'the'wall of the sleeve have their ends seated in, and frictionally engaging thebottom of, the groove so that, when'the sets'crews are: loosened, the sleeve and barrel may be relatively V rotated, the setscrews being thereafter tightened to securely lock the barrel and sleeve to ether against further relativ rotation. Axially concentric with the lock barrel I2 is a separate adjustable lock barrel I! provided with external threads which mesh with the internal threads 8 of the sleeve,and journaled in the bore 1, in concentric relation with the lock barrels l2 and I I. is a cylindrical end plug I8 having a peripheral groove [9 thereon in which the sleeve flange H seats so that the plug is prevented from movement out of the end of the sleeve. A pair of guide rods 2|, having their opposite ends pressed into suitable sockets reamed into the barrel [2, and the plug l8 so as to fix the rods in' place, pass freely through apertures therefor formed in the movable lock barrel l'l so that the latter may slide on the guide rods; in the space between the confronting ends of the lock, barrel l2 and the plug l8. It will be seen that if the setscrews l6 are loosened and the sleeve 4 isrevolved relative to the lock barrel l2, movement of the screw threads 8 will cause the movable lock barrel H to be shifted axially in a selected direction toward either the lock barrel l2 or the plug I8. V

Extending axially through the lock barrel l2, and positioned eccentricallywithrespect to the axis thereof, is a bore 22 in whichis journaled one section 23v of a cylindrical lock rotor, having atone end a flange 24, which rests in a counterbore 26 formed in the face of the'lock barrel l2 so as to prevent relative axial movement between the lock barrel and rotor in one direction, and provided with a longitudinally extending slot 21, of complex cross-sectional configuration into which the shank of a key 28 of complemental cross-sectional shape may be inserted.

A bore 29, axially aline with the bore 22, is provided in the movable lockbarrel ll in which is journaled a second separate section 3 of, the lock rotor which is provided at each end with radially extending flanges 32 seated in counterbores 33 so that the rotor section 3| is secured in the movable lock barrel against axial movement relative thereto but is movable, as the, lock barrel is moved toward either the lock barrel I2. or the plug I8. The rotor section BI is provided with a slot 34 through whichv the shank of, the key 28 may slidably pass. The plug I8. is provided with an eccentrically positioned bore 36, axially alined with the bores 22 and 29 of the look barrels l2 and IT, in which is journaled a third, section 31 of the lock rotor which also has extending axially therethrough a slot 33 for thereception of the key 28. A pair of radially spaced rods 39, best shown in Figure 3, are. secured at. their ends in the sections 23 and 3'! of the rotor and pass freely through suitable apertures. provided therefor in the rotor section 3]. These rods tie all of the rotor sections for rotation together as a unit. A lever 41 secured to the end.

46 and 41. is provided with the usual tumbler notches 48 which are cut to various depths and which receive the rounded lower ends of the lower tumbler sections 49. These tumbler sections are of such length that, when the key is in position in the slot provided therefor in the rotor, the upper end of each, as is shown in Figure 3, is positioned so that the rotor is free to be rotated in its bore. Also slidably mounted in each tumbler bore, above the lower tumbler section therein, is an upper tumbler section 5|, and each bore contains a coil spring 52 which engages the end of each upper tumbler section so as to resiliently of the rotor section 31 by screws 42 is provided 7 for engagement with the retractible bolt. of the lock in any desired manner so thatwhen the lock rotor is. revolved by the key 28, the lock bolt may .be moved to retracted or extended positions as desired. V .1

. The lock barrel. I2 is providedwith a plural ity, Preferably four, of transversely extending, axially .spaced, cylindrical tumbler bores 43, which are axially alined with similar bores 44 formed in the rotor section 23, and the movable lock barrel I! and its. rotor section 3! are alsoprovided with like axially alined: tumbler bores urge the latter downwardly into intimate contact with the lower tumbler section. Both of the lock barrels I2 and I! are provided with dovetailed slots 53 in which are inserted plates 54 which engage the upper ends of the springs 52 so as to retain the latter in the tumbler bores. When the key 28' is withdrawn from the lock rotor the springs 52 will urge each tumbler downwardly in its bore so as to project the upper section 5| of each tumbler into the mating bores of the rotor whereupon the rotor and lock barrels will be pinned together against relative rotation.

It will be seen that all of the structure contained in the lock barrel I2 is of conventional and well-known construction and that the only way the combination of the lock may be changed, as regards the first four tumblers reading from right to left in Figure 1, is by making the corresponding key notches 48 shallower or deeper with a corresponding lengthening or shortening of the lower tumbler sections 49. This obviously requires that the entire lock be dismantled so that original key. The new key is then inserted fully in the lock rotor, the setscrews [8 are loosened,

the sleeve 4 is manually-rotated so as to shift the movable lock barrels I1 axially so as to aline the tumbler with the newly cut key notch, which condition will become evident when the key may be rotated, and then tightening the setscrews IE to secure the sleeve in its new position. While it is preferable that the newly cut key notch be the same depth as thecorresponding notch of the old. key, so that the tumbler will release when it is alined with the notch, it is not absolutely essential that this dimension be micrometrically duplicated Since, if the notch is slightly deeper than the old one, the end of the tumbler, when the sleeve 4 has been rotated sufliciently to permit free rotation of the lock rotor by the key, will rest against a slopingv side. of the notch rather than the bottom thereof thus positioning the plane of division of the tumbler correctly with respect to the periphery of the rotor. The amount of axial adjustment of the movable lock barrel. should not be less than A; of an inch sothat at least as many combination changes may be obtained as is: possible with the use of a key notch of the same depth.

The most important advantage gained by use of the lock of my invention is-that combination The upper edge of the key shank be seen that it is not wholly impossible for a person who ordinarily knows nothing of lock construction, with the aid of simple and easily followed directions, to easily fit a new key to and change the combination of the lock of my invention. While I have shown and described a single movable lock barrel at the rear of the lock structure, it is obvious that the movable lock barrel may be duplicated at the forward end of the look so that the range of combination changes may be greatly multiplied.

Having thus described my invention in detail, what I claim as new and desire to secure by Letters Patent is:

A look comprising a tubular sleeve provided with an internal screw thread, axially alined separate lock barrels and a plug positioned in and rotatable relative to said sleeve, a first of said lock barrels having a peripheral screw thread meshing with said internal screw thread of the sleeve, a pair of spaced guide rods secured at their ends in said plug and a second of said lock barrels, said first of the lock barrels being in slidable engagement with said guide rods, setscrews in said sleeve and engaging said second of the lock barrels for securing the latter and the sleeve against relative rotation, a rotor comprising separate cylindrical sections journaled respectively in said first and second lock barrels and in said plug, a pair of spaced second guide rods secured at their ends in the rotor sections of said plug and second look barrel and being in slidable engagement with said first of the lock barrels, tumblers normally locking said rotor and lock barrels together against relative rotation, said rotor sections having alined key way openings, and said tumblers normally projecting into said openings.

2. In a lock, a sleeve, a pair of axially alined lock barrels rotatably mounted in said sleeve, said barrels having alined bores whose axes are alined lock barrels rotatably mounted in said sleeve, one of said barrels being in threaded engagement with said sleeve, said barrels having alined bores whose axes are parallel with the barrel axis, lock rotors arranged within said bores, said rotors and barrels having transversely disposed openings alined with each other, a pair of tumblers arranged within each of said openings, a bar slidably connecting said lock barrels, said rotors having axially alined key openings, the tumblers of said rotors normally projecting into said key openings, the second of said barrels being rotatable within said sleeve, and means for holding said barrel against rotation.

4. In a lock, a fixed sleeve, a pair of axially alined lock barrels mounted within said sleeve, one of saidbarrels being movable toward or away from the other barrel, said barrels having alined bores whose axes are parallel with the barrel axis, lock rotors arranged within said bores, said rotors and barrels having transversely disposed openings alined with each other, a pair of turnblers in each of said alined openings, means for holding said barrels against relative rotation, said rotors having axially alined key openings, the tumblers of said rotors normally projecting into said key openings, and means for holding the second of said rotors in fixed engagement with said sleeve,

JO N CHING- 

